New study helps trace hazardous chemicals in salmon farms

New study helps to identity synthetic chemicals in oceans waters and in feed that risk harming farmed salmon and consumers.

The American Chemical Society journal Environmental Science & Technology featured research by Carla Ng, assistant professor of civil and environmental engineering at Pitt’s Swanson School of Engineering as reported in Science Daily.

Dr. Ng tracked the presence of a class of synthetic flame retardants called polybrominated diphenyl ethers (PBDEs), an additive which was used increase fire resistance in consumer products in electronics, textiles and plastics. She also says that food is an important source of human exposure to hazardous chemicals.

Dr. Ng’s study compared a variety of factors to find the best predictor of the chemical in farmed salmon.

She said, “We found that feed is relatively less important in areas that already have high concentrations of pollutants in the environment. However, in otherwise clean and well-regulated environments, contaminated feed can be thousands of times more significant than the location of the farm for determining the PBDE content of salmon fillets.”

“Hot spots are places identified as having high levels of pollutants,” says Dr. Ng. “As these chemicals circulate through the environment, much ends up in the ocean. It’s extremely important to pay attention to the sourcing of ocean commodities and areas where pollutant concentrations are particularly high.”

Despite restrictions on their use, PBDEs continue to be released into the environment in places places like China, Thailand, and Vietnam because of their long lifetime and abundance in consumer goods.

“The international food trade system is becoming increasingly global in nature and this applies to animal feed as well. Fish farming operations may import their feed or feed ingredients from a number of countries, including those without advanced food safety regulations,” explained Dr. Ng.